Convert your RGB color format to HEXA format.
Convert your RGB color format to RGBA format.
Convert your RGB color format to HSV format.
Convert your RGB color format to HSL format.
Convert your RGB color format to HSLA format.
Validate JSON content and make it looks good.
Get approximate IP details.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Get all possible details about an SSL certificate.
Ping a website, server or port..
Take an IP and try to look for the domain/host associated with it.